@Bean
public FlatFileItemReader<Person> reader() {
    return new FlatFileItemReaderBuilder<Person>()
        .name("personItemReader")
        .resource(new ClassPathResource("sample-data.csv"))
        .delimited()
        .names("firstName", "lastName")
        .targetType(Person.class)
        .build();
}

public class PersonItemProcessor implements ItemProcessor<Person, Person> {

    @Override
    public Person process(Person person) {
        return new Person(
            person.firstName().toUpperCase(),
            person.lastName().toUpperCase()
        );
    }
}

@Bean
public JdbcBatchItemWriter<Person> writer(DataSource dataSource) {
    return new JdbcBatchItemWriterBuilder<Person>()
        .sql("INSERT INTO people (first_name, last_name) VALUES (:firstName, :lastName)")
        .dataSource(dataSource)
        .beanMapped()
        .build();
}

@Bean
public Step step1(
        JobRepository jobRepository,
        DataSourceTransactionManager transactionManager,
        FlatFileItemReader<Person> reader,
        PersonItemProcessor processor,
        JdbcBatchItemWriter<Person> writer) {

    return new StepBuilder("step1", jobRepository)
        .<Person, Person>chunk(3, transactionManager)
        .reader(reader)
        .processor(processor)
        .writer(writer)
        .build();
}

@Override
public void afterJob(JobExecution jobExecution) {
    if (jobExecution.getStatus() == BatchStatus.COMPLETED) {
        jdbcTemplate
            .query(
                "SELECT first_name, last_name FROM people",
                new DataClassRowMapper<>(Person.class)
            )
            .forEach(person ->
                log.info("Found <{}> in the database.", person)
            );
    }
}

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public class Car {
    public static int totalCars = 0;  // Static
    private String model;             // Instance

    public Car(String model) {
        this.model = model;
        totalCars++;
    }

    public String getModel() {
        return model;
    }
}

Car c1 = new Car("BMW");
Car c2 = new Car("Audi");

System.out.println(Car.totalCars);  // 2
System.out.println(c1.getModel());  // BMW
System.out.println(c2.getModel());  // Audi

double result = Math.sqrt(25);  // بدون ایجاد شیء

#کاربر_مبتدی

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